Caption: Portrait of Paul (Adrien Maurice) Dirac (1902- 1984), British physicist and Nobel Laureate. Dirac studied electrical engineering at Bristol, before studying theoretical physics at Cambridge in 1926. In 1932 he was made Lucasian Professor of Mathematics at Cambridge. In his studies of atomic structure, Dirac concluded that there had to be a positively- charged equivalent of the electron, later showing that the same equations held true for other charged particles. Thus Dirac first proposed the existence of anti-matter. His work led to sharing the 1933 Nobel Prize for Physics with Schrodinger. Many anti-particles have since been discovered experimentally.